Monday, December 17, 2007

The Health of Nations

A very interesting recent publication is the OECD's Health at a Glance, a summation of measurements and indicators of health status for the 30 OECD member countries.

There will be reliability and comparability issues with some of the statistics provided in the report. Generally, the high-level outcome data such as life expectancy should be accurate (although there are quibbles about things like the definition of a live birth). The detailed information such as pay rates of doctors and items of equipment should probably be taken more lightly. It's evident just by looking at these details for New Zealand that the OECD has in some cases obtained only partial information or used unreliable sources.

The publication provides demographic and economic data for context. As we know, and periodically get angsty about, New Zealand is 22nd out of 30 in GDP per capita. We're now outstripped by Spain, and just hovering above Greece. In many respects, the indicators in the report reflect this status, and place us alongside countries like the Czech Republic and Korea. New Zealand health expenditure per capita is the 10th lowest in the OECD.

Despite this, our overall life expectancy is the 11th highest in the OECD. For life expectancy at age 65, we're 11th for females and 5th for males.

This relatively good health does not appear to be due to healthy living or judicious behaviours. We're about in the middle for tobacco and alcohol consumption, but right near the bottom for several other measurements. We're 10th worst for children's dental health, 9th worst for suicide, 8th worst for deaths from road accidents, and 6th worst for obesity.

The areas we do best may surprise some people. While New Zealanders are used to moaning about our health system 'going downhill', it actually appears to do better than average.

In 30-day mortality after hospital admission for a heart attack, New Zealand is number 1. We don't do so well on the same indicator for stroke, where we are 20th. A couple of clinical people I've talked to have expressed skepticism about these results, suggesting that we may not do either as well or as badly as depicted. Australia mirrors us closely, coming 2nd for heart attack and 19th for stroke, so there may be mesurement or other issues confounding the data.

Elsewhere, our relative five-year survival rate for colorectal cancer is 4th (out of only 12 countries that can measure it) and 3rd out of 19 for cervical cancer. For breast cancer survival, New Zealand is at the OECD average, but has made the biggest improvement of any country since the last measurement period

Another of the things measured is 'perception of health status', which is the percentage of adults who report being in good health. Where do you think New Zealand would come here? Yes, we're Number 1*.

The amusing thing is that this range of dry statistics more or less reconstructs the popular stereotypes. There's evidence that the Kiwi 'she'll be right' attitude persists -- people are generally positive about their health despite not living officially very healthy lifestyles. They also like to grumble about a health system that, in its traditional role of responding to acute illness, does well by international standards.

It's interesting to look at how other countries do on the various indicators. As expected, the United States comes out near the top on some (overall expenditure and resources, some clinical outcomes) and very low down for others (obesity, road accidents, low infant birth weight, and overall life expectancy). Like New Zealand, it has positive perceptions of health status. It also has a low suicide rate and is one of five countries (along with New Zealand, Iceland, Turkey and Mexico) to have a fertility rate above two children per woman.

Another interesting case is Japan, which has the highest life expectancy of all but comes right at the bottom for perceptions of health, fertility, and suicide. People with a knowledge of Japan may have some comment on those statistics.

For some indicators, the English-speaking countries cluster together. The highest mortality rates for asthma are, in order, the UK, Australia, Ireland, New Zealand and the US. I'm not sure that anyone fully understands why this is. For obesity, the UK, US, Australia and New Zealand are four of the bottom six. The other two are Mexico and Greece, which is somewhat surprising.

One thing that interested me was the data on smoking rates. The two more developed countries that have the highest rates of smoking are Greece and the Netherlands. These countries do have higher rates of lung cancer, but are in the middle on overall life expectancy. They are also two of the countries with the lowest suicide rates. Make of that what you will.

The pattern that appears most apparent, however, is that the 'fringe' OECD countries with a GDP per capita between $10,000 and $20,000 are grouped near the bottom on many of the indicators. Up to a certain point, wealth appears to matter to health status. Past about $25,000 per capita, however, it doesn't seem to make much difference.

* As explained in the report, there are comparability issues between NZ, the US, Australia and Canada, and the other countries, but even so New Zealand is top among this group.